diff --git a/drivers/net/usb/sr9700.c b/drivers/net/usb/sr9700.c
index 5a53e63d33a60995ea8023474e664f6fc14017a5..3164451e1010cc80a67e2fddc89a9e59a6721cab 100644
--- a/drivers/net/usb/sr9700.c
+++ b/drivers/net/usb/sr9700.c
@@ -413,7 +413,7 @@ static int sr9700_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
 		/* ignore the CRC length */
 		len = (skb->data[1] | (skb->data[2] << 8)) - 4;
 
-		if (len > ETH_FRAME_LEN || len > skb->len)
+		if (len > ETH_FRAME_LEN || len > skb->len || len < 0)
 			return 0;
 
 		/* the last packet of current skb */